Afaik: One way to tell whether you have the combox or MULF if you can't visually see it is to see whether a regular iPod cable (not the bmw dongle) and an iPod with mp3s will play over the stereo. If so, it's the combox. If not, it's the MULF.
Euro spec wide mirrors; sport wheel + paddles; staggered sport rims with Conti ExtremeContact DW. JL Audio 600/6 + technic harness; Gladen Audio 8" Woofers + musicarnw adapters; Morel Hybrid Ovations. For sale: front and rear MSport springs; rear MSport struts.